Search Publications
The GUAPOS project - V: The chemical ingredients of a massive stellar protocluster in the making
Testi, L.; Mininni, C.; Lorenzani, A. +9 more
Most stars, including the Sun, are born in rich stellar clusters containing massive stars. Therefore, the study of the chemical reservoir of massive star-forming regions is crucial to understand the basic chemical ingredients available at the dawn of planetary systems. We present a detailed study of the molecular inventory of the hot molecular cor…
Properties of the gas escaping from a non-isothermal porous dust surface layer of a comet
Mottola, S.; Küppers, M.; Thomas, N. +6 more
Estimation of the properties of the sublimation products leaving the cometary nucleus is one of the significant questions in the study of the dusty-gas flow following the Rosetta mission. It is widely assumed that the temperature of the water molecules emitted is the temperature of ice directly exposed to the surface. However, it is the simplest n…
Cliff collapse on Comet 67P/Churyumov-Gerasimenko - I. Aswan
Davidsson, Björn J. R.
The Aswan cliff on Comet 67P/Churyumov-Gerasimenko collapsed on 2015 July 10. Thereby, relatively pristine comet material from a depth of $\sim 12\, \mathrm{m}$ was exposed at the surface. Observations of the collapse site by the microwave instrument Rosetta/Microwave Instrument for Rosetta Orbiter (MIRO) have been retrieved from 8 months prior to…
Deciphering cometary outbursts: linking gas composition changes to trigger mechanisms
Mall, Urs; De Keyser, Johan; Berthelier, Jean-Jacques +9 more
Dust and gas outbursts are recurrent cometary phenomena, playing a crucial role in shaping the coma. Proposed outburst trigger mechanisms include cliff collapse, pressure pockets, and amorphous-to-crystalline phase transition of water ice; however, the underlying processes remain inadequately understood. In this study, we analyse Rosetta/ROSINA da…
Cliff collapse on Comet 67P/Churyumov-Gerasimenko - II. Imhotep and Hathor
Davidsson, Björn J. R.
Cliff collapses on Comet 67P/Churyumov-Gerasimenko expose relatively pristine nucleus matter and offer rare opportunities to characterize ice-rich comet material. Here, Microwave Instrument for Rosetta Orbiter (MIRO) observations of two collapsed or crumbling cliffs in the Imhotep and Hathor regions have been assembled. The empirical diurnal anten…
Imaging polarimetry of comet 67 P/Churyumov-Gerasimenko: homogeneous distribution of polarization and its implications
Kolokolova, Ludmilla; Moreno, Fernando; Snodgrass, Colin +8 more
Comet 67P/Churyumov-Gerasimenko (67P) become observable for the first time in 2021 since the Rosetta rendezvous in 2014-2016. Here, we present pre-perihelion polarimetric measurements of 67P from 2021 performed with the Very Large Telescope (VLT), as well as post-perihelion polarimetric measurements from 2015 to 2016 obtained with the VLT and the …
Detection and characterization of icy cavities on the nucleus of comet 67P/Churyumov-Gerasimenko
Lamy, Philippe; Groussin, Olivier; Faury, Guillaume +1 more
We report on the detection of three icy cavities on the nucleus of comet 67P/Churyumov-Gerasimenko. They were identified on high-resolution anaglyphs built from images acquired by the Optical, Spectroscopic, and Infrared Remote Imaging System instrument aboard the Rosetta spacecraft on 2016 April 9 and 10. Visually, they appear as bright patches o…
On the similarity of rotational motion of dust particles in the inner atmosphere of comets
Fulle, M.; Moreno, F.; Rotundi, A. +6 more
In situ measurements of individual dust grain parameters in the immediate vicinity of a cometary nucleus are being carried by the Rosetta spacecraft at comet 67P/Churyumov-Gerasimenko. For interpretation of these observational data, a model of dust grain motion as realistic as possible is requested. In particular, the results of Stardust mission a…
Charging effects on Rosetta dust measurements
Deca, Jan; Horányi, Mihály
Dust particles released from comet 67P/Churyumov-Gerasimenko collect electrostatic charges. Their motion is influenced by the electric fields induced by the flow of the solar wind and by the charging of the Rosetta spacecraft itself. Dust grains with sufficiently low tensile strength might even be destroyed en route from the nucleus to Rosetta. A …
Cold electrons at a weakly outgassing comet
Henri, P.; Galand, M.; Deca, J. +1 more
Throughout the Rosetta mission, cold electrons (<1 eV) were measured in the coma of comet 67P/Churyumov-Gerasimenko. Cometary electrons are produced at ~10 eV through photoionization or through electron-impact ionization collisions. The cold electron population is formed by cooling the warm population through inelastic electron-neutral collisio…